Galictis vittata, Schreber, 1776

Don E. Wilson & Russell A. Mittermeier, 2009, Mustelidae, Handbook of the Mammals of the World – Volume 1 Carnivores, Barcelona: Lynx Edicions, pp. 564-656 : 636-637

22.

Greater Grison

Galictis vittata

French: Grand Grison / German: Grofser Grison / Spanish: Grison

Taxonomy. Viverra vittata Schreber, 1776 ,

Surinam.

Four subspecies are recognized.

Subspecies and Distribution.

G. v. vittata Schreber, 1776 — the Guianas and Venezuela.

G. v. andina Thomas, 1903 — Bolivia and Peru.

G. v. brasiliensis Thunberg, 1820 — Brazil.

G. v. canaster Nelson, 1901 — Mexico to Colombia and Ecuador.

Descriptive notes. Head-body 47.5-55 cm, tail 16 cm; weight 1.4-3.3 kg. The Greater Grison has a long body and short limbs. The pelage is smoky gray on the upper sides; the face, throat, undersides, and all four limbs are black. A white stripe extends across the forehead and down the sides of the neck, separating the black of the face from the gray or brown of the back. The skull is strong and massive. Dental formula: I 3/3, C 1/1, P3/3.M1/2=34

Habitat. Greater Grisons are found in virgin and secondary low-elevation rainforests, lower montane forests, upland monte alto forests, tropical dry forests, closed deciduous forests, cerrado, yungas woodlands, shrub woodlands, chaco, palm savannah, secondary growth, open fields, plantations, and partially flooded rice fields adjacent to ranches. They are often found near rivers, streams, and wetlands, from sea level to 1500 m elevation, but mostly below 500 m. However, on the east slopes of the Andes Mountains in Bolivia they range up to 2000 m. A radio-collared female spent 27-8% of her time in open habitats (69-2% of her prey came from there); the remaining 72-2% was spent in closed woodlands and forests (where she obtained 27-8% of her prey).

Food and Feeding. The diet includes small mammals, birds, eggs, amphibians, reptiles, invertebrates, and fruit. In Venezuela, seven stomachs contained remains of diurnal rodents (Sigmodon alstoni), a lizard (Ameiva ameiva), a dove (Zenaida auriculata), and an eel-like fish. Two other stomachs contained an opossum (Didelphis marsupialis), an unidentified rodent, a lizard (Ameiva ameiva), and an amphibian (Colestethus auriculata). In Para, Brazil, a Greater Grison was observed carrying a large toad (Bufo marinus) in its mouth, apparently unaffected by the toad’s toxic skin glands. In Panama, a Greater Grison was seen pursuing an Agouti (Dasyprocta punctata) at 08:15 h; another Agouti was attacked in a river at midday. In Peru, a Greater Grison was observed eating a piranha-like characin fish. In north-eastern Brazil, Greater Grisons are major predators of Rock Cavies or Mocos (Kerodon rupestris), which they attack in their burrows. The stomachs of two males and two females contained Moco remains and another species of cavy (Galea spixii). Greater Grisons hunt alone, in pairs, or in small family groups. An adult female was seen travelling in association with a nearly grown male and a three-fourths grown female.

Activity patterns. Primarily diurnal, but occasionally active at night. A captive male from Ecuador was nearly 100% diurnal, with a rest period of several hours at midday. Three captive Greater Grisons in Panama were very active in the early morning and late afternoon and rested for four to five hours around midday. Greater Grisons forage during the day at Cocha Cashu, Peru. However, in Venezuela, a radio-collared individual was active for 10-12 h per day, mostly at night (77-1% of the time); all sightings were in the daytime (06:00-11:25 h). Rest sites are undertree roots or in hollow logs, underground burrows, or rock cavities.

Movements, Home range and Social organization. Primarily terrestrial, but also excellent swimmers and able to climb trees. In Venezuela, two individuals were observed climbing into a tree, and on another occasion, a female and a young climbed 2 m into a palm tree, while an adult male waited below looking upward. The two grisons scratched around in the tree, knocking down wood and debris, which were examined by the male. Greater Grisons are mostly solitary, but occasionally travel in pairs or small groups. One female in Venezuela had a home range of 4- 2 km * She traveled 1 km (straight line) between consecutive daily restsites and moved 2-3 km per 24-h period. Population densities have been estimated at 1-2-4 individuals/km?, but radio-tracking data suggests much lower densities.

Breeding. Gestation is around 39 days. Litter size is one to four. Offspring have been observed in March, August, September, and October. A neonate female, with umbilical cord still attached, weighed less than 50 g. She was covered in short fur and her eyes were closed. The eyes opened after two weeks, and by three weeks she could eat meat. Full growth was reached by four months. The testes of three captive males descended at c. four months of age.

Status and Conservation. Classified as Least Concern in The IUCN Red List. Greater Grisons are considered endangered in some parts of their range, such as Mexico and Costa Rica. In Venezuela, they are threatened by hunting and habitat destruction. Greater Grisons occur in medium (860 ha) and large (36,000 ha) fragments in Brazilian Atlantic forests, but are absent from small (60-80 ha) patches of forest. Their fur has no commercial value, but skins and live animals are sold as decorations or pets.

Bibliography. \Wozencraft (2005), Yensen & Tarifa (2003a).

Figures

On following pages: 21. Lesser Grison (Galictis cuja); 22. Greater Grison (Galictis vittata), 23. Marbled Polecat (Vormela peregusna); 24. Saharan Striped Polecat (/ctonyx libycus); 25. Zorilla (Ictonyx striatus); 26. African Striped Weasel (Poecilogale albinucha).

Subspecies and Distribution. G. v. vittata Schreber, 1776 — the Guianas and Venezuela . G. v. andina Thomas, 1903 — Bolivia and Peru . G. v. brasiliensis Thunberg, 1820 — Brazil . G. v. canaster Nelson, 1901 — Mexico to Colombia and Ecuador .